In the time since the FY2015 submission, we have identified 252 individuals between age 20 to 103 years of age with both toenail and fecal samples (Table 1). To examine the microbial association with age with little to no effect by health condition, we selected individuals with exceptional health status based on the following criteria: No established genetic diseases, no difficulty performing self-care or instrumental activities of daily living, a score of 12 on the short physical performance battery of lower extremity function (10 or more in persons over 90 years old), ability to walk 400meters and no shortness of breath while performing daily living, no history of cardiovascular disease, diabetes, active cancer, metabolic disease, severe hormonal dysfunction , neurological diseases, kidney or liver diseases, severe gastrointestinal diseases, musculoskeletal disorders, severe psychiatric condition, long-term antibiotics, antiviral, corticosteroid, immunosuppressant, H2 blockers, pain medication, sensory deficits, no cognitive impairment, WBC<12,000/uL, platelets 100,000-600,000/uL, hemoglobin 11g/dL, creatinine clearance > 50cc/min, bilirubin < 1.5mg/dL (unless Gilberts disease), no abnormal levels of SGOT/sGPT/alkaline phosphatiase and albumin >3.4g/dL. We are in the midst of preparing for sample transfer to the University Maryland Institute for Genome sciences. Table 1. Number of subjects with both fecal and toenail samples by age group. Age group: Women, Men, Total 20-30: 3, 4, 7 30-40: 4, 4, 8 40-50: 8, 10, 18 50-60: 10, 5, 15 60-70: 34, 22, 56 70-80: 32, 31, 63 80-90: 43, 35, 78 90+: 2, 5, 7 Total: 136, 116, 252